1. Field of the Invention
The present invention relates to a mobile crusher.
2. Description of Related Art
A mobile crusher including a crusher that crushes raw materials has been typically known. In such a mobile crusher, raw materials conveyed by a feeder are crushed to a predetermined size by the crusher to be discharged by a discharge conveyor. When a detector for detecting the raw materials on the feeder and crusher detects an idling of the feeder or crusher (the idling means that a work implement is operated without raw materials or crushed materials), a controller slows engine speed down to idling rotational speed during the idling, thereby reducing fuel consumption (Document 1: JP-A-2000-136739). Alternatively, a controller may control fuel injection quantity depending on the weight of raw materials mounted on the feeder irrespective of the presence of the raw materials within the crusher (Document 2: JP-A-5-184968).
However, in the mobile crusher as disclosed in Document 1, only the engine speed is controlled and the speed of the work implement is not controlled. Thus, a deceleration rate of the work implement speed during the idling is the same as a deceleration rate of the engine speed. Since the engine idling rotational speed is approximately 50% of normal speed, the work implement speed is decelerated by approximately 50%. However, approximately 50% deceleration of the work implement speed is not sufficient for power reduction.
In the mobile crusher as disclosed in Document 2, engine output is decreased when the weight of the raw materials mounted on the feeder is reduced even while the raw materials are crushed by the crusher. Thus, an operation quantity of the crusher is reduced and therefore crushing efficiency is reduced.